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Table 1 Specification of the MEP-e

From: Medium-energy particle experiments—electron analyzer (MEP-e) for the exploration of energization and radiation in geospace (ERG) mission

Parameter Value Notes
Energy range 7–87 keV  
Energy resolution 8% FWHM of the electrostatic analyzer response
Energy steps 16 steps per scan  
Sensor field of view 360°(azimuth) × 3.5°(elevation) ~ 3.5°(azimuth) × 3.5°(elevation) per detector Azimuthal gaps exist between detectors FWHM
Number of APDs 16 Circularly aligned
Geometric factor 6.6 × 10−5 cm2 sr keV/keV per detector APD efficiency not included
Time resolution 4 s for the 3-D distribution function 250 ms for one energy scan 15.6 ms for one energy step ~ 1.5 μs for the S-WPIA data For nominal spacecraft spin (8 s)
Sensor size ϕ318 mm × 395 mm Including PSU/CPU
Sensor mass 8.2 kg  
Power consumption 21 W Including DC/DC converter efficiency
Data rate 1.756 kB per one energy scan